Water Supply Scheme System Design for Peri Urban Areas of Punjab using EPANET

Abstract Water is indispensable for human life and without water, life cannot exist on earth. Every person required 33 to 35-gallon water per day for drinking and demotic purpose. But due to lack of quality, inefficient water supply designs, intermixing of sewage water and unlined sewage water system, quality of water is deteriorated specially in recent decades and affecting a number of people. In present study, it was inevitable to design a water supply system for selected area to provide safe water supply design for a small community. For this purpose, a study area was selected named as chak.no. 253 RB, Samundri Road Faisalabad. The existing water supply system of the village was built 30 years ago with the problems of leaky pipes, mixing of sewerage water with drinking water was causing water-borne diseases like Diarrhea, Cholera, Giardiasis, Typhoid fever, Schistosomiasis. A computer software abbreviated as EPANET (Environment protection agency network) was used to design a water supply system of the area providing input parameters to the software. For this a profiling survey was conducted to determine the length of pipes and the elevation of each junction. The other input parameters such as the diameter of pipes, pipe network map, head losses were provided. Conclusively, EPANET gave a detailed water supply system plan for specific design period. By adopting this design provided by detailed surveys of the area and EPANET will help to control intermixing of sewage water which ultimately improves the quality of water. The new design is based on technology by using modern techniques (Software). It will provide save and continue supply of water to community. It will also reduce the cost of water billing, leakage, decrease the diseases rate and improve the life standard of people’s lives in that area.


Introduction
Water is a key factor to alive and is indispensable for all living organisms. A person can only live for a matter of a few days without water. So, life cannot exist on earth without it. Considering the quantity of water, about 2.8% of the total amount of water on earth is freshwater of which only 0.6% is groundwater. The rest is available in the oceans and mainly seas, while a negligible amount as soil moisture. Out of the 2.2%, 2.15% is found in the form of glaciers and ice sheets while the remaining 0.05% is available as surface runoff. It is estimated that each person on earth is required 20 to 50 liters of clean safe water each and every day. The quality of water is also a critical factor after quantity and more importantly is the concept of clean water. This clean water is to be used for drinking, cooking, simple hygiene, etc. Providing good and safe drinking-water is world-wide considered to be a fundamental issue for public health protection and must be the primary objective of water supply systems. The best water supply system is a system of engineered hydrologic and hydraulic components which prevents water-related problems and yields a good quality water according to the needs of community [1,2]. The water distribution system is a framework consisting of aspect such as pipes, junctions, tanks, reservoirs, pumps and valves etc. [3,4]. It is necessary to supply water to the public because Water scarcity is among the major issue faced by many societies worldwide in the 21st century, approximately 1.2 billion people live in areas of physical water scarcity, and 500 million people are approaching this tragic situation [5]. Efficient water supply is of foremost importance in spanning the existing one or in designing a new water supply system [6]. Tube wells are concentrated in the Punjab Province which accounts for 93% of all private tube wells in Pakistan. The ratio of groundwater recharge to discharge is 0.8 and as a result, rapid decline in the water tables has been reported in many parts of the country that's why the water scarcity is the major issue is Pakistan [7,8]. To fulfil the water demand of the rapidly growing population we need to provide the adequate and uniform quantity of water through the designed network of pipes [9]. Potable water is not well distributed in the world. 1.8 million deaths are attributed to unsafe water supplies every year. Water supply systems must meet requirements for public(domestic), commercial, and industrial activities [9,10].
Numerous computer tool were developed, out of all the tools available EPANET which is freely available became most popular and convenient for the effective design of complex pipe networks [11]. EPANET is a computer software that performs extended period simulation of hydraulic and water quality behavior within pressurized pipe networks [9]. EPANET is used to designed to be a research tool for improving or enhancing our understanding of the movement and fate of drinking water constituents within the designed distribution system. By the use of EPANET that is by filling the data into it about several nodes, junctions, pipes, demand and supply (flow), tanks and reservoir, we designed the water distribution system for the study area [12]. EPANET tracks the flow of water in each pipe, the pressure at every node, the height (head) of water in each tank or reservoir, and the concentration of a chemical species like chlorine which is a highly efficient disinfectant and is added to public water supplies to kill disease-causing pathogens such as bacteria, viruses, and protozoans, that commonly grow in water supply reservoirs, on the walls of water mains or pipes and in storage tanks, throughout the network during a simulation period comprised of multiple time steps (Kanth, Manasa, Rupesh) [13]. The EPANET was very useful for the proper designing of the whole water supply system of that village, it also helped to find the present situation of water supply by given the calculated data or values to it which gave the detailed information of running system [5]. The water supply pipes are splits and harm. The blending the sewer water in drinking water ordinary. The water conveyance siphons are old, harmed and have low productivity. There is no weight, stream measure is introduced on the siphon outfall pipe. The core objective of present study is to design and develop a plan for equitable distribution of sanitary water for a small community using EPANET software. To achieve this major objective certain secondary The distribution system designed here is Gridiron system. This is also known as interlaced system or reticulation system. The mains, sub-mains and branches are all interconnected with each other. Use of EPANET and filling the data into it about several nodes, junction, demand (flow), elevation, tanks or reservoirs and pipes. In this system, the water is pumped at a constant rate and stored into an elevated distribution tank, from where it is distributed to the consumers by the action of gravity.

Data requirement
The core objective is design and develop the water supply system for this specific area to minimize the rate of water losses, leakage, its cost and make sure to 100% supply of safe water for all purpose. To complete this task, a questionnaire was prepared to get the information about the people living in the house, number of water tanks, water storage capacity, the number to refill the tank in 24hrs and the problems faced by people due to present damage water distribution system. It was observed that the water distribution system was built 30 years ago and presently water supply lines are damage. Mixing of sewerage water with drinking water was occurring due to leaky pipes and open sewerage system. It was concluded that the old, inefficient and poor water supply system was causing water-borne diseases as discussed earlier. It was inevitable to design and replace the existing water supply system for that area to avoid all the problems discussed earlier. The materials used for this study include; contour map by doing profile survey, road network map, water demand, population, water supply network and also finally EPANET software. The total water demand which was obtained after calculate the population for next 30 years for that study area is 468125 gallons, also the study area comes under the rural settlement. By doing a survey in that village the total water demand was used 137.60 L/C/D or 35 US Gallons is calculated. The base demand is calculated at each particular junction is 35 US Gallons. The elevation data of each node is taken by performing the profile leveling. After that, the following steps were carried to analyses the hydraulic modelling of the water distribution network:

Survey of the study area for estimating water demand.
The survey of the area was conducted to get the idea of water consumption per house in 24hrs. To achieve this task a questioner paper was prepared to get the information about people living the house, their water storage tank capacity, and the amount of water used for drinking and domestics purpose. The questioner paper prepared to get all above information from people of that area is pined in index. The remarks also added in this questioner paper by people about that old, leaky and poor water supply system.

Population forecasting
The current population of the village is near about 7735. The previous record shows that there is a constant increase in the village population. The average rate of birth is 188 per year and average death rate is 48 per year. The percentage change in population is 0.79%. After 30 years the population of the study area will be 13375, Growth rate in Figure 2 was calculated by Arithmetic mean method. The birth and death rates of the village population are shown in the table and by graphs.

Arithmetical Increase Method
This method is use to forecast the population of the old area; which population is grow with slow rate. The change in population every year should be constant almost. The study area is small and average population growth rate is constant [14]: The rate of change of population with respect to time is constant.

Materials and Measure the lengths of streets
The lengths of streets are measured to get the idea of pipe length required. The pipes used in design are plastic pipes due to feasible in transportation, low prices and do not required heavy machinery for installation and easy to handle. Plastic pipes, if required in modest quantity, are also reasonably feasible to manufacture from imported raw materials. Plastic pipes have distinct advantages over other pipes due to its light weight, availability in long lengths, ease in transporting (to and on the site) and handling and installation. Plastic pipes, due to its longer lengths, have the general advantage that performance is less affected by poor installation. Plastic pipes are very suited for machine installation. Prices for small diameter pipes of all materials are usually comparable. For large diameter pipes, concrete and cast iron are the cheapest choice and plastic most expensive. According to the survey, the length of streets of the study area is,  Sheep & goat 5 to 10, 02 Total consumption of water = 655408 gallon No of pump use in design = 02 Flow for one pump = 327704 gallon.

Calculation the diameter of pipe lines
The scheming of the pipe diameter is chief commission. The precise diameter of pipeline is imperative because the pipe line diameter is unswervingly related with the flow and financial plan. In water supply design the diverse pipes of different diameter are use. The great pipes lines of enormous diameter have the high rate as relate to the unimportant diameter of the pipeline. The choices of pipe for a right diameter is done through the flow, required in pipeline. For large volume of flow, the pipe of the large diameter is required as well for squat flow, the pipe of the small diameter is required in design.
There are several scientific equations are used to catch the diameter of the pipe lines by using the flow, slop and roughness of the pipe material. The objective of all these mathematical equations are only find the suitable diameter of the pipe according to the given flow.
As the flow is non-uniform and pipe are plane, so the equation, uses to find the diameter the pipe is [15]:

Elevation and base demand values for each Node
The elevation value from mean sea level is assign to each value with suitable slop, measure by the profile leveling. The elevation is in ascending order to give a suit able slope for gravity flow of water in pipe lines. The base demand is average or nominal demand for water by the main category of consumer at the junction, as measured in the current flow units. With the help of elevation data that was collected by profile leveling about the nodes, joints, junctions, discharge, diameters of pipes. The elevations of joints describe the flow direction of high potential to low potential.

Pipe Description
The pipes material is plastic and has the length according to the streets length as describe above in table 1. The roughness of the plastic pipe material is 140-150 [16]. Plastic pipes have unmistakable focal points over different funnels because of its lightweight, accessibility in long lengths, ease in shipping and dealing with and establishment. Plastic creased pipes, because of its more extended lengths, have the general bit of leeway that exhibition is less influenced by the poor establishment. Plastic channels are appropriate for machine establishment. the plastic strip gives an incredible sparing in transportation, taking care of, and establishment

Results and Discussion
By the use of EPANET various relation are being found between elevation, velocities, flow, pressure, head, demand, etc. these relations can be understood by studying the graphs plotted.

Pressure vs Flow Distribution
This is the graph between Pressure and Flow. which shows the variation of Flow in different pipes concerning the Elevation provided to the particular pipeline. The color of each pipe is show the value of the Flow in GPM. The scale is according to the color. The Red color show the Flow in pipe is equal or above than 100 GPM and blue color show the rang of flow equal or less than 25 GPM. The pressure at the Nodes is also describe by the color. The Red color show the pressure in node is equal or above than 100 psi and blue color describe the pressure at Node is equal or low than 25psi. With passage of the time, the color of the pipe and Node is change as Flow in pipes and pressure is change in Nodes respectively. The different values of Elevation and velocity are also given in figure 3.

Pressure vs Velocity Distribution
This is the graph between Pressure and Velocity, which shows the variation of velocity in different pipes concerning the Elevation provided to the particular pipeline. The color of each pipe is show the value of the Velocity in feet per second. The scale is according to the color. The Red color show the Velocity in pipe is equal or above than 2.00 feet per second and blue color show the rang of Velocity equal or less than 0.01 feet per second. The pressure at the Nodes is also describe by the color. The Red color show the pressure in node is equal or above than 100 psi and blue color describe the pressure at Node is equal or low than 25psi. With passage of the time, the color of the pipe and Node is change as Velocity in pipes and pressure is change in Nodes respectively. The different values of Elevation and velocity are also given in figure 4.
Design of water supply system by using EPANET This graph shows the pressure at all nodes after running the system after 1hr with respects to the distance between the nodes. The peak pressure is at j67 after one hour is 103.54 psi and minimum pressure at Node j11 is 91.20 psi. The variation in the pressure at all nodes is varies within the sequence.

Distribution of velocity at Link
This graph shows the variation at the velocity at links. The velocity is continuing increase from starting.

Distribution of the Flow at Link
This graph shows the distribution of the Flow in Links after running the system at one hour. The flow at pipes is continue increase until it is constant.

Flow in links w.r.t Time
The variation of the flow in links with respect to time is shown in graph. The various links are selected from the system. The peak flow in all links after one and four hours occurs. In peak hour the pressure at system is maximum as well as flow. The flow pattern in selected links is almost common.

System Flow Balance
This system flow balance describes the relation between the consumption and total water demand. As the system run successfully, so the water demand is equal to the water consumption for next upcoming 30 years.

Pressure Distribution at selected Nodes
The distribution of the pressure at different node is show by the system in graph. The pressure is sudden drop after running the system 1hr and after 4hrs. the pressure is rise smoothly from 00hrs to 1hrs to for stabilization. Then it decreases continue until at end.

Distribution of velocity at selected Links
The graph shows the distribution of the velocity at selected links from the system with respect to time. The rate of velocity in each pipe is depend on its internal diameter. The pipes of different diameter carry the different velocity rate. At link66 the velocity at 00hrs is 3.7-3.8 fps. The variation in velocity of flow is varies with respect to time.